Process of preparing keto-alcohols



Patented ay; 21,1929.

PATENT OFFICE.

ANGELO KNORB, OF BERLIN, AND ALBERT -WEI SSENBOBN, F PUTSDAM, GERMANY, ASSIGNOBS, BY KESNE ASSIGNMENTS, TO WINTHBOP CHEMICAL COMPANY, INC., OF ,NEW YORK, N. Y., A CORPORATION QB NEW YORK. i a

t PROCESS OF PREPARING KETO-ALCOHOIJS.

Ho Drawing. Application filed January 21, 1927, Serial No. 152,871 and in Germany January 19, 1 926.

This invention relates to prepartion of keto-alcohols.

The condensation of aldehydes with ketones has been much investigated but no prac- 5 tical mode of carrying out the condensation has been found.

Condensation by means of aqueousalkalies, alkali carbonates or alkali cyanides, so far as any condensation is attainable, gives very poor yields. p

Condensation by means of gaseous hydrochloric acid leads to compounds containing processes for the chlorine, the separation of which from the mass gives rise to difiiculties.

The poor'results which have been obtained in this particular condensation are due to the fact that the reaction between aldehydes and ketones roceeds only very gradually, wherethe condensing agents; thus the desired reaction is smothered by aldol condensation and resinification, and, besides, the ketols which are at first produced are not stable towards the usual condensing agents. 2o' Special precautions, for example dissolving the aldehyde and ketoneto be condensed in a solvent immiscible with water and using the condensing agent in aqueous solution, are

tedious and irregular in effect, not always leading to the-desired result in spite of the 'ketol produced are withdrawn from the in-- jurious action of the condensing agent.

By the present invention these difliculties manner: 1 The condensation is conducted in the absence of water and with the use of an alkali metal compound of a 1.3-ketol as the condens-- ing' a cut. Advantageously, there 'is used as the a kali metal compound of the ketol, one which is produced by treating with an anh drous solid alkali metal hydroxide in the co (1 I theketone which is to becondensed. "To the of ketone,'"for instance, to the solution of the alkali metal com ound of diacetone-alcohol in acetone,-the a dehyde is added gradually while cooling well. The condensation pro ceeds ra idl and hardly any by-product is produced. %orexample, when acetone is used, almost the onl by-product is diacetonealcohol which may e used for making fresh condensing agent. The mixture produced by rated aliphatic ketones.

rated aliphaticketones.

as the a dehydesare very sensitive towards fact that in this manner the aldehyde and the p are overcome by operating in the following v Arylsubstituted unsaturated solution of the condensing agent'in'excess the reaction. is easily worked up; the alkali is precipitated by means of carbon dioxide,- the excess of ketone is separated by distillationand. the condensation product is separated from the residue by fractional distillation, for instance, in a vacuum, the yield'bemg ood. The process is applicable for ex.- ampe to the following condensations: Saturated aliphatic aldehydes saturated aliphatic ketones.

Saturated aliphatic aldehydes-l-unsaturated aliphatic ketones. I Unsaturated aliphatic aldehydes-Fsatu- Unsaturated aliphatic aldehydes+unsatu- Saturatedaliphatic ketones. 1 I

Unsaturated aliphatic aldehydes+ arylalkyl ketones. i

Saturated aliphatic aldehydes+s'aturated aliphatic ring ketones. Unsaturated aliphatic 'aldehydes-tsatw' rated aliphatic ring ketones.

Saturated aliphatic aldehydes+unsaturated aliphatic ring ketones.

. Unsaturated aliphatic aldehydes-l-un'saturated aliphatic ring ketones.

Arylsubstituted saturated aldehydes+ saturated ketones.

Arylsubstituted unsaturated aldehydes+ 35 saturated ketones.

Arylsubstituted saturated aldehydes+-unsaturated ketones.

aldehydes arylalkyl aldehydes+ unsaturated ketones.

Arylsubstituted saturated 'aldehydes arylalkyl ketones. I p

lsubstituted unsaturated aldehydes aryla kyl ketones. V Arylsubstituted saturated aldehydes+saturated aliphatic ring ketones.-

7 Arylsubstituted unsaturated aldehydes+ saturated aliphatic'ring ketones. Arylsubstituted saturated aldehydes+un-" saturated aliphatic ring ketones. a V Arylsubstituted unsaturated aldehydes+ unsaturated aliphatic ring ketones.

.The condensation products are useful as erfumes or as intermediate products in makmg perfumes p The invention is illustrated by the followingv examples, the parts being by weight Example 1.- To 1000 parts of dry acetone excess of acetone is separated by distillation.

The distillation residue contains, besides diacetone-alcohol, hydracetylacetone in good yield, resinous by-products having been formed only in insignificant proportion.

Emample 2.41%; the .well cooled solution of 10 parts of solid potassium hydroxide in 1000 parts of dry acetone there are added gradually, as prescribed in Example 1, 200 parts of propyl aldehyde, while stirring. The product is worked up as described in Example 1. There is obtained a good yield of l1exanol-(4)-on-(2) which boils at 80-85 C. under 10 mm. pressure. Example 3.500 parts of methylethyl ketone are mixed with 10 parts of solid potassium hydroxide and brought into reaction in l the cold, and gradually, with 200 parts of butyric aldehyde. The product is worked up as'described in Example 1, whereby 300 parts of inethylethyl ketone are recovered and there are obtained 280 parts of'octanol- (5) -on -(3), which boils at 95-96 C. under Patenthi9. 1,714,378.

10 mm. pressure.

In similar manner crotylidene acetone is obtained by condensation of acetone and eroton aldehyde to the corresponding ketol and gradually subsequently splitting ofi' water; also, cinnamylidene acetone (boiling point 155 C. under 12 mm. pressure) from the word "under" ANGELO uuok'n ET AL.

which consists in condensing an aldehydewith a ketone in the absence of water by means of an alkali metal compound of a 1.3- ketol as condensing agent.

2. The process which comprises dissolvingin the cold a powdered alkali metal hy dioxide in an excess of a ketone and causing an aldehyde to act in the cold upon this solution.

3. The process which comprises dissolving about 10 to 20 pounds of potassium hydroxide in about 1000 pounds of dry acetone and adding about 200 to 300 pounds of an aldehyde while cooling.

4. Process which comprises adding 20 parts by weight of powdered potassium hydroxide to 1000 parts by weight of dry ace' tone at about 5 0., cooling the resulting solution and slowly adding thereto in small portions at a time 300 parts by weight of acetaldehyde, thereafter passing into the re-' action mixture carbon dioxide, separating the resulting solution from the resulting precipitate, and separating the excess of acetone from said solution by distillation.

In testimony whereof we aflix our signatures.

DR. ANGELO KNORR.

DR. ALBERT WEISSENBORN.

, Granted May .21, 1929. m

It ia hereby certified that Jppearein the printed ip ecification of the above numbered patent requiring correcfioi a follower insert thennmeral "10";

, rage'z; line 43, after and that the said Letters 'Patent should be read' with this-correction therein thnt'the seme nayconfomi to the record of the case in the Patent Gffice.

Signedind sealed this 18th day tum, A. 1).,1'929.

(sun I M. J. Moore, Acting Commisaionerof Patents.

CERTIFICATE OF CORRECTION.

Patent Ne, 1,714,378. Granted May 21, 1929, to

ANGELG KNORR ET AL.

Kt is hereby certified that error appears in the gsritttezi epeeificatien of the above numbered patent requiring eorrectien as feltews: Page 2, time 43, after the were! "under" insert the numeral "10"; and that the said Letters Patent shotttd be read with this eerrection tizerein that the same may content! te the record ef the ease in the Patent Office.

Signed and. sealed this 18th day of June, A. R 19296 M. J. Moore, (geat) Acting Cemmissiener of Patents. 

